THE POISON GARDEN website

Pontifications on Poison

Being some ramblings on events associated with poisonous plants.

Monday 28th November 2011

I shall have to rethink parts of one of my talks after
stumbling across a paper suggesting that a couple of things I’ve
been including in my
‘Medical Murderers’ presentation are not as clear cut as I
thought.

The stumbling started when I happened upon a 1999 paper by
two French toxicologists who reviewed cases of human poisoning
due to plant extracts before looking at a new method of
determining the concentration of plant poisons post mortem.

I followed one of their references, a 1996 paper entitled
‘Toxicity following accidental ingestion of Aconitum containing
Chinese remedy’
(the abstract is here), and during a further search to see
if I could find the full paper found, instead, a 2006 paper
entitled ‘Aconitine involvement in an unusual homicide case’
(available in full here).

It describes a case from Belgium where a woman used
Aconitum napellus, monkshood, to murder her husband. The
case began when a car was discovered with its front in a ditch
next to a road. The driver was dead behind the wheel. The
appearance that this was a simple car accident either caused by
the driver collapsing at the wheel or caused some other way but
killing the driver on impact was soon shown not to be the case
when a crude, partially burnt fuse was found hanging from the
fuel tank. Closer examination of the body revealed signs of
asphyxia, strangulation and frequent blunt force trauma to
various parts of the body.

The police investigation into the circumstances of the man’s
death made no progress for five years but, then, DNA testing was
conducted that implicated the man’s wife. When questioned she
confessed to his murder at their home some 100km from the crash
site.

The woman had boiled up the leaves and stalks of three
Aconitum napellus plants and added the liquid obtained, together
with prescribed sleeping tablets, to a bottle of red wine. The
woman said her husband showed no symptoms of poisoning so she
went to bed. Three and a half hours later she found him dead in
a chair. For some reason, she decided to move the body upstairs,
using ropes and a roll of carpet before deciding to dispose of
it and bringing it back downstairs and out to the car. This trip
up and down the stairs explained the many bruises found on the
body.

She positioned it in the driver’s seat and then sat on the
dead man’s lap as she drove the 100km to the place where she
drove the car into the ditch and then tried, unsuccessfully, to
set fire to it. She then took a taxi home.

It does seem a little strange that the case took so long to
solve. And here’s where we start to get into the changes I’ll
need to make to my talk. The underlying theme is the development
of forensic science. The notion that, two hundred years ago, we
were only just beginning to identify the alkaloids that make
poisonous plants toxic and we had almost no tools to identify
them if used to effect a poisoning but, today, our science is so
sophisticated and so mature that there is no chance of a poison
going undetected.

But, although these chemicals can be identified the important
first step is to look for them. In this Belgian case, the only
tests conducted, at first, were to establish how much the
deceased had been drinking and if he had used drugs. Once the
wife had confessed, toxicologists were able to establish the
presence of the alkaloids of monkshood, aconitine and its
relatives, but we’ll never know if they would have found them if
they didn’t know what they were looking for.

I usually say that Aconitum napellus is not a useful murder
weapon because it has a unique taste that will make people aware
that something about their food or drink is not right. But, in
this case, the victim seems to have happily drunk the bottle of
red wine without comment. So that’s something else I’ll have to
modify in my presentation.

My key line, that getting away with murder is about no-one
realising murder has occurred, also needs some modification.
Clearly, in this case, foul play was suspected but the wife came
very close to getting away with it. Again, we’ll never know if
the police would have been able to make a convincing case
against her had she not confessed. So, getting away with murder
may just be a matter of hoping that the investigation of your
crime is not thorough.